High-capacity hydrogen storage through molecularly restructured and confined hydrogen hydrates

Abstract

In the future landscape of sustainable energies and in combating global climate challenges, hydrogen plays a crucial role in both stationary and portable energy systems that currently supply 18 % of the total energy demand. High-capacity, safe, and cost-effective hydrogen storage is critical for advancing the hydrogen economy but remains a dauting challenge. A range of advanced material systems including metal hydrides, metal-organic frameworks, and 2D materials have been explored in efforts to achieve high storage capacity, but high operating pressures, low charging/discharging rates, and energy intensive discharging processes have hindered their development and deployment. Here, we report a green material paradigm for high storage capacity with fast charging/discharging and ambient temperature discharging. The material platform is a modified zeolite with rationally tuned pores and modified surface chemistry that exhibits long-term stability and stores hydrogen gas in the form of hydrogen hydrates. The selected pore dimensions enhance the hydrogen solubility through restructuring of water molecules, and the surface chemistry of the material leads to enhanced double donor-acceptor bonds with water molecules for enhanced hydrogen storage capacity. The material enables hydrogen storage in hydrogen hydrate form at 8–10 bar dropping the required storage pressure by two orders of magnitude lower compared to state-of-the-art materials and addresses long-standing hurdles of high operating pressure and slow formation kinetics of hydrogen hydrates providing a promising platform for hydrogen storage.